The invention relates to a male or female quick coupling element, as well as a quick coupling including such an element.
The invention more particularly relates to the quick couplers used to couple pressurized fluid pipes. With a quick coupler, when coupling two pressurized fluid pipes, a male element and a female element are nested in one another to create a pressurized fluid circulation tunnel. This coupling requires pushing back valve flaps which, in this case, belong to each of the male and female elements of the coupler. These flaps are subject to the internal pressure of each coupling element, this pressure being able to be high and led to increase in its environment, to the point of hindering the maneuvering of the coupler, inasmuch as the operator may experience difficulties in overcoming the resisting force exerted by the pressure of the fluid inside the coupling elements, against the flaps. For example, for a coupler whereof the flap has an outer diameter of 5 mm, the force to be exerted to connect the male and female elements of the coupler, one of which is coupled to a pipe at 160 bars, is about 330 newton (N).
To overcome this difficulty, it is known, for example from FR-A-2,657,138, to arrange a fluid channel that is opened, during the coupling of the male and female elements of the coupler, owing to a member actuated from the front face of the coupling element. This allows part of the fluid present in the coupler to escape and the pressure of the fluid inside the coupler to be balanced relative to the ambient pressure. This facilitates the withdrawal of the moving valve flaps and makes the operator's manipulations easier.
However, the system of FR-A-2,657,138 is based on the incorporation, within a central part of the coupler, of a non-return flap formed by a bead bearing on a sealing seat. Such as non-return flap is relatively bulky, which is not compatible with all coupler sizes. In particular, in some couplers with a small diameter, only a reduced space is available in the central part of each male or female element, which does not make it possible to accommodate the known mechanism. Furthermore, the larger the diameter of the coupler is, the more the flaps may have extensive surfaces subject to the internal pressure of the coupler and the higher the resisting forces are with respect to the nesting.
The invention more particularly aims to resolve these drawbacks by proposing a new structure for a male or female quick coupling element, in which a fluid passage may be opened during the coupling of the male and female elements of the coupler, without requiring a bulky construction.